Answer:
f'(x) = 
Step-by-step explanation:
i) f(x) = 9 / x
ii) f'(x) = 

Every 60 seconds in Africa a minute passes together we can stop this
If it increases at 3.9% a month, then in a year it increases 46.8%.
This is because a year has 12 months and so take 3.9(12)=46.8